Sri Lankan forces fought their way into the Tamil Tigers' final stronghold of Mullaittivu on Sunday and were battling to take control of the town, the military said.

The capture of Mullaittivu would expel the tigers, who once controlled a wide swath of northern Sri Lanka, from the last major town under their control.

"According to the battlefield sources, troops of 593 Brigade lead by Lieutenant Colonel Jayantha Gunarathne have made a surprise attack across the Nanthikandal lagoon and entered the Mullaittivu town area this morning. Infantrymen of 7 Gemunu Watch (7 GW) lead by Lieutenant Colonel Chaminda Lamahewa have been in first to enter the town amid heavy terror resistance" the military said.

The Mullaittivu town is situated in a narrow stretch of a land between Nanthikandal lagoon and the Indian Ocean. The town fell to the terrorists in 1996 and since then LTTE established its main military base there.

"Troops are negotiating pockets of fighting here and there," military spokesman said.

In recent weeks, the Sri Lankan military has captured the LTTE administrative capital of Kilinochchi and forced them into a broad retreat and boxed them into a tiny pocket of territory in the northeast.

The Tamil Tigers took control of the town in 1996 when they overran a military camp there and killed nearly 1,000 soldiers.

The troops' entrance into the town after 13 years came after the government ordered all government-paid administrators in the rebel-held north to leave the territory in preparation for a final assault on the insurgents.